1. Technical Field
The invention relates to a system of attaching an injection system to a turbojet combustion chamber base.
The combustion chambers of turbojets comprise an inner wall and an outer wall connected at their upstream end via an annular base to define a combustion chamber base. Injection systems evenly distributed over the periphery of the combustion chamber base deliver a mixture of air and fuel that is burned to provide combustion gases.
Each injection system comprises a venturi in which the air and the fuel mix. A bowl, situated downstream of the venturi, has the function of breaking up the jet of air/fuel mixture coming out of the venturi. In addition, a deflector protects the chamber base from the flames of the combustion chamber.
2. Description of the Prior Art
In a known embodiment (U.S. Pat. No. 4,584,834), the injection system is mounted from downstream, that is to say via the rear of the turbojet. In a system of this type, the injection system is welded onto the chamber base directly or via an intermediate part; the deflector and the bowl are welded onto the injection system. If the weld situated between the injection system and the bowl fails, the latter impacts the combustion chamber and the downstream portion of the engine, particularly the HP turbine, which may lead to the engine exploding. In the same manner, if the weld situated between the injection system and the deflector fails, the latter will, in a first time, be held by the bowl but the additional forces exerted on the bowl will ultimately cause the weld situated between the injection system and the bowl to fail also so that the two parts will be thrown simultaneously into the combustion chamber and into the downstream portion of the engine with the same consequences as hereinabove.
In addition, beside the risk of a weld rupturing, it is not easy to dismantle an injection system in order to carry out its maintenance or replacement. Specifically, this operation requires removing three welds at the same time, which is awkward and most frequently requires the sacrifice of a part, usually the injection system itself. The object of the present invention is an injection system and an attachment method that remedy these disadvantages.